1. Field of the Invention
The present invention relates to a semiconductor integrated circuit device and a semiconductor device. For example, the present invention relates to a semiconductor integrated circuit device that controls a power supply voltage provided by an external power supply circuit.
2. Description of the Related Art
In recent years, semiconductor devices have been significantly miniaturized. The miniaturization has resulted in a frequent problem attributed to a manufacturing variation among semiconductor devices. That is, the manufacturing variation varies, for example, operating speed and power consumption during standby, among semiconductor chips.
Thus, a technique is known which varies the value of a power supply voltage depending on the properties of the whole semiconductor chip to set the operating speed and the power consumption at values suitable for the product. Such a technique is disclosed in, for example, Jpn. Pat. Appln. KOKAI Publication Nos. 2006-120686 and 2004-363374. Since the properties of the semiconductor device also vary depending on the power supply voltage, these techniques vary the power supply voltage to offset the variation in properties caused by the manufacturing variation.
However, the above techniques vary the value of the power supply voltage on the basis of the properties of the whole semiconductor chip. Thus, the variation in power supply voltage may not be suitable for all the individual semiconductor circuits contained in the semiconductor chip. The variation may even affect some of the semiconductor circuits.